Detailed answer

Short answer: In Missouri a co-owner cannot convey more than their own share. If a co-owner attempts to sell the entire property without the other owner’s agreement, the buyer generally takes only the selling co-owner’s interest — not clear title to the whole property. The non-selling co-owner has several civil remedies (including actions to partition, quiet title, seek injunctive relief, and obtain damages) and may have criminal remedies if the deed was forged or the sale was fraudulent.

How co-ownership works (basic concepts for beginners)

• Owners typically hold property as tenants in common or as joint tenants. Tenants in common each own a separate share and can sell that share without the other co-owner’s consent. Joint tenancy includes rights of survivorship and has different consequences if one tenant sells.
• When one co-owner signs a deed conveying the whole property without the other owner’s signature, that deed conveys the seller’s share only. It usually cannot extinguish the non-selling co-owner’s ownership interest by itself.

Primary civil remedies in Missouri

1. Quiet title / declaratory relief. The non-selling co-owner can ask a court to declare the true ownership interests and remove any improper cloud on title. A quiet title action clarifies who owns what and prevents future challenges to the non-selling owner’s rights.
2. Partition action. If co-owners cannot agree about use, sale, or division of the property, Missouri law allows a co-owner to seek partition. The court can physically divide the property (partition in kind) or, if physical division is impractical, order a sale and divide the proceeds among owners according to their interests. See Missouri’s partition statutes: RSMo § 525.010 and following. For the statutory text, see: https://revisor.mo.gov/main/OneSection.aspx?section=525.010 and https://revisor.mo.gov/main/OneSection.aspx?section=525.020
3. Injunctive relief / lis pendens. If a sale is imminent or a fraudulent sale is underway, a co-owner can ask the court to stop the sale (temporary restraining order or preliminary injunction) and file a notice of pendency (lis pendens) so potential buyers are on notice a dispute exists. This helps protect the non-selling owner’s interest while litigation proceeds.
4. Accounting for rents, profits, and damages. If the buyer or selling co-owner has excluded the non-selling co-owner from possession, the non-selling co-owner may seek an accounting for rents and profits or money damages for wrongful exclusion.
5. Rescission or reformation in cases of fraud or mistake. If the sale was procured by fraud, forgery, or material misrepresentation, a court may rescind the conveyance or reform the deed and award damages. Forgery of a deed or submission of fraudulent documents can also be criminal conduct.

What the buyer usually gets — and limitations

When one co-owner sells without the other, a buyer generally receives only the seller’s fractional interest. The buyer typically does not obtain clear title to the entire parcel simply because a deed purports to convey everything. That means the buyer may own, for example, 50% of the property while the non-selling co-owner still owns the rest. The non-selling owner can then pursue partition or other remedies to enforce their rights.

When criminal charges may apply

If a deed was forged, a signature was fabricated, or the sale involved clear criminal fraud, the non-selling co-owner can report the conduct to local law enforcement or the county prosecutor. Criminal charges (for forgery, fraud, or related offenses) are separate from civil claims and can run in parallel with civil litigation.

Practical next steps (recommended sequence)

1. Obtain a certified copy of the deed from the county recorder and any recorded instruments showing ownership.
2. Review title history (or have an attorney/title company do so) to confirm what interest the seller actually conveyed.
3. Send a written demand letter asserting your rights and asking for corrective action if appropriate (signed sales contract rescinded, deed corrected, etc.).
4. If necessary, file a civil action: quiet title/declaratory relief or a partition action (see the Missouri partition statutes linked above). Ask the court for temporary injunctive relief if a sale, eviction, or other irreparable harm is imminent.
5. If you suspect forgery or criminal fraud, preserve documents and consider contacting law enforcement or the county prosecutor’s office to report the matter.

Timing and costs

Litigation timelines vary. Partition and quiet title actions often take several months and can last a year or longer depending on complexity, whether the parties settle, and court schedules. Costs include filing fees, attorney fees, appraisal and survey costs, and potential costs of a court-ordered sale.

When negotiation or buyout may be better

Sometimes co-owners can negotiate a buyout of the selling co-owner’s share or agree to a voluntary sale. Negotiation can save time and reduce legal costs compared with contested litigation.

Relevant Missouri statute (partition): RSMo Chapter 525: https://revisor.mo.gov/main/OneSection.aspx?section=525.010

Helpful hints

• Immediately get certified copies of any recorded deed and the property’s chain of title from the county recorder.
• Preserve all documents, emails, texts, sale contracts, and any communications about the sale.
• Do not accept oral assurances — get everything in writing, and consider sending a demand letter through an attorney.
• If you are in possession of the property, document your occupancy and any damages or lost rents (photos, receipts, statements).
• Consider a title search or a title company opinion early; that clarifies what rights changed (if any) when the deed recorded.
• File for injunctive relief quickly if a sale or eviction is imminent — timing matters for emergency relief.
• Be aware that a buyer who purchases a seller’s share for value typically receives only that share. A subsequent court action (partition or quiet title) will sort out how to proceed.
• If you suspect forgery or a criminal scheme, contact law enforcement and an attorney right away to preserve evidence and protect your rights.
• Talk to a real estate attorney in your county experienced with partition, quiet title, and co-ownership disputes to evaluate the best remedy for your situation.

Disclaimer

This article explains general legal principles under Missouri law to help you understand possible remedies. It is not legal advice and does not create an attorney-client relationship. Laws can change and the appropriate remedy depends on the specific facts. For advice about your situation, consult a licensed Missouri attorney.